A conventional probe capable of measuring an external surface, an internal surface, a hole diameter, and the like of a measuring object is disclosed in Japanese Patent No. 3075981 (patent document 1). FIG. 18A and FIG. 18B are diagrams showing a configuration of a conventional three-dimensional shape measurement device probe 310 disclosed in patent document 1. The probe 310 is a probe for measuring a side surface extending in a vertical direction or substantially vertical direction of the measuring object, and cannot measure the surface extending in a horizontal direction or substantially horizontal direction.
The measuring operation is carried out as below with the probe 310. In FIG. 18A, when the probe 310 moves in YZ directions with respect to a surface to be measured S, an arm 303 with a stylus 301 tilts along a substantially X direction according to the displacement of the surface to be measured S in the X direction. Laser light is irradiated from a semiconductor laser light emitting unit 306 to a mirror 302 on an upper surface of the arm 303, and the tilt of the arm 303 is detected by light position detecting means 307 based on reflected light from the mirror 302. The entire probe 310 is moved in the X direction so that the detected tilt becomes constant, an X coordinate measurement value of the entire probe 310 is obtained from the movement amount, and a displacement amount of the stylus 301 detected by the light position detecting means 307 is added to the X coordinate measurement value, so that an X coordinate indicating the displacement amount of the surface to be measured S in the X direction is measured with high precision. Thus, the position in the Y direction of the measuring object cannot be measured with the probe 310 due to its structure.
In view of such a problem, the applicant filed an application relating to a probe capable of measuring the hole shape and the surface shape of a measuring object and of being inclined in any horizontal direction (Japanese Patent Application No. 2005-105915, issued as Japanese Unexamined Patent Publication No. 2006-284410). FIG. 19 shows a structure of the shape measurement device probe disclosed in the application.
In FIG. 19, a shape measurement device probe 351 is arranged in a shape measurement device 371, and a measuring surface contacting member 360 with a stylus 361 is connected so as to swing in any direction of the horizontal direction with a supporting point 363 as the center with respect to an attachment member 362. A connecting member 364 is made up of a coil spring, and supports a central axis of the measuring surface contacting member 360 in a vertical direction during non-measurement time and generates force to press the stylus 361 against the measuring object during measurement time. As shown in FIG. 20, the tilt about the X, Y axes of a mirror 365 fixed on an upper part of the measuring surface contacting member 360 is detected by an inclined angle detecting part 366. The entire probe 351 is operated by the shape measurement device 371 with respect to the measuring surface so that the press-in amount of the stylus becomes constant, and furthermore, the XYZ positions of the probe 351 are detected and the values thereof are added to the displacement of the stylus in the horizontal direction converted from the tilt of the mirror 365 to detect the position of the stylus with high precision. According to such a configuration, the surface in any direction of the measuring object can be measured without rotating the measuring object.